Ultra DMA data burst timing requirements 2

Table 5.16 Ultra DMA data burst timing requirements (2 of 2)

NAME	MODE 0		MODE 1		MODE 2		MODE 3		MODE 4		COMMENT
	(in ns)		(in ns)		(in ns)		(in ns)		(in ns)

	MIN	MAX	MIN	MAX	MIN	MAX	MIN	MAX	MIN	MAX	(see Notes 1 and 2)

tZIORDY	0		0		0		0		0		Minimum time before driving
											IORDY

tACK	20		20		20		20		20		Setup and hold times for DMACK-
											(before assertion or negation)

tSS	50		50		50		50		50		Time from STROBE edge to
											negation of DMARQ or assertion of
											STOP (when sender terminates a
											burst)

Notes:

1) Unless otherwise specified, timing parameters shall be measured at the connector of the sender or receiver to which the parameter

applies (see Note 5 for exceptions). For example, the sender shall stop generating STROBE edges t after the negation of

RFS

DMARDY-. Both STROBE and DMARDY- timing measurements are taken at the connector of the sender.

2)All timing measurement switching points (low to high and high to low) shall be taken at 1.5 V.

3)tUI, tMLI and tLI indicate sender-to-recipient or recipient-to-sender interlocks, i.e., one agent (either sender or recipient) is waiting for

the other agent to respond with a signal before proceeding. t is an unlimited interlock that has no maximum time value. t is a

UIMLI

limited time-out that has a defined minimum. t is a limited time-out that has a defined maximum.

4) Special cabling shall be required in order to meet data setup (t ) and data hold (t ) times in modes 3 and 4.

DSDH

5) Timing for tDVS and tDVH shall be met for all capacitive loads from 15 to 40 pf where all signals have the same capacitive load value.

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